Laser fuze is susceptible to aerosol interference,which causes false alarm in the fuze.The research of laser anti aerosol interference is always a difficult problem to be solved.The components of aerosols in the atmospheric environment are diverse,so it is of great significance to study the laser echo of aerosols with different materials,and smoke and cloud are typical representatives of aerosols of different materials.In this paper,based on Mie scattering theory and Monte Carlo random logic method,single and multiple scattering models of laser smoke and cloud fog are established respectively.The echo characteristics of laser with different pulse widths of 10 ns,20 ns and 50 ns,different materials of aerosol smoke and cloud,and different scattering times arecompared and analyzed,and the scattering echo law of laser with different pulse widths under different materials of aerosol is obtained.The simulation results show that the smaller the laser emission pulse width and the greater the aerosol visibility,the better the discrimination effect between target echo and aerosol echo；the transmittance of laser in cloud is higher than that of smoke,and the reflectivity is lower than that of smoke；the attenuation degree of laser in smoke is higher than that in cloud particles.This conclusion can provide a research idea for studying the back scattering echo characteristics of laser fuze in aerosol environment and improving the anti interference capability.